3 files changed, 9 insertions, 5 deletions
diff --git a/src/datavisualization/engine/shaders/surfaceFlat.frag b/src/datavisualization/engine/shaders/surfaceFlat.frag
index a8a3dbb1..1f2a3822 100644
--- a/src/datavisualization/engine/shaders/surfaceFlat.frag
+++ b/src/datavisualization/engine/shaders/surfaceFlat.frag
@@ -1,8 +1,10 @@
-#version 150
+#version 120
+
+#extension GL_EXT_gpu_shader4 : require
 
 varying highp vec3 coords_mdl;
 varying highp vec3 position_wrld;
-flat in highp vec3 normal_cmr;
+flat varying highp vec3 normal_cmr;
 varying highp vec3 eyeDirection_cmr;
 varying highp vec3 lightDirection_cmr;
 
diff --git a/src/datavisualization/engine/shaders/surfaceFlat.vert b/src/datavisualization/engine/shaders/surfaceFlat.vert
index 7e248d02..0d39f6bc 100644
--- a/src/datavisualization/engine/shaders/surfaceFlat.vert
+++ b/src/datavisualization/engine/shaders/surfaceFlat.vert
@@ -1,4 +1,6 @@
-#version 150
+#version 120
+
+#extension GL_EXT_gpu_shader4 : require
 
 attribute highp vec3 vertexPosition_mdl;
 attribute highp vec3 vertexNormal_mdl;
@@ -10,7 +12,7 @@ uniform highp mat4 itM;
 uniform highp vec3 lightPosition_wrld;
 
 varying highp vec3 position_wrld;
-flat out highp vec3 normal_cmr;
+flat varying highp vec3 normal_cmr;
 varying highp vec3 eyeDirection_cmr;
 varying highp vec3 lightDirection_cmr;
 varying highp vec3 coords_mdl;
diff --git a/src/datavisualization/engine/surface3drenderer.cpp b/src/datavisualization/engine/surface3drenderer.cpp
index 337d4604..22ad3c7f 100644
--- a/src/datavisualization/engine/surface3drenderer.cpp
+++ b/src/datavisualization/engine/surface3drenderer.cpp
@@ -1716,7 +1716,7 @@ bool Surface3DRenderer::updateSmoothStatus(bool enable)
 {
     if (!enable && !m_flatSupported) {
         qWarning() << "Warning: Flat qualifier not supported on your platform's GLSL language."
-                      " Requires at least GLSL version 1.5.";
+                      " Requires at least GLSL version 1.2 with GL_EXT_gpu_shader4 extension.";
         enable = true;
     }